"The clean-up operation is mainly targeted at accounts that do marketing in a coercive way," Weibo said.

China has recently grown into the world's largest internet market, and Chinese companies such as Alibaba has capitalised on their strength in the home market to raise funds and expand globally.

With the user base being the key gauge to assess social networking companies, Weibo has recently been hurt by steady loss of users to WeChat. Weibo's user base declined 9% during 2013 to 281 million, according to data from the China Internet Network Information Center.

Weibo is 32% owned by Alibaba, which is already in a spat with Tencent. WeChat blocked promotion of Kuaidi Dache, Alibaba's taxi hailing service, a week ago, Xinhua reported.